Machines for operating on shoes



April 3, 1956 5. J. FINN ET AL 2,740,142

MACHINES FOR OPERATING 0N SHOES Filed March 28, 1952 8 Sheets-Sheet 2fmzemars Sidney J. Film Wcz/Ze/"L.Benedz'cf Hans FSafzaefel Jl? JohnWfiursh B ez'r April 1956 s. J. FINN ETAL 2,740,142

MACHINES FOR OPERATING 0N SHOES Filed March 28, 1952 8 Sheets-Sheet 5fnvemors Sidney JF'mn T Valzer L. Benedz'cf fzcms FSc/zaefer, Jr: JohnWfiursh By thi/"A 6g April 1956 s. J. FINN ETAL 2,740,142

MACHINES FOR OPERATING 0N SHOES Filed March 28, 1952 8 Sheets-Sheet 4Inventors Sidney J. Finn T Valzer L. Benedict Hans FSchaefer; Jr JohnWHurs/z April 3, 1956 $1. FINN ETAL 2,740,142

MACHINES FOR OPERATING ON SHOES Filed March 28, 1952 8 Sheets-Sheet 5JQg? 6 412- 40 2/ /2 4% 4J6 455 464K154 Q i V I 1' 4067 4)? ya," I: 246m If 2: /66 Z55 Z95 W 5% i I 90 -59;

Sidney J. F'z'rm T Vblzer L.Benedicz Ha r25 FSc/zae fer, J1? John WHarsh y orneg April 1956 s. J. FINN ETAL 2,740,142

MACHINES FOR OPERATING 0N SHOES Filed March 28, 1952 8 Sheets-Sheet 6 1%fnvenfars Sidney J. F'z'nn WczZze/"LBeneaz'cz Hans FSa/zaefexyJr: John Wursh April 3, 1956 s. J. FlNN ETAL 2,740,142

MACHINES FOR OPERATING 0N SHOES Filed March 28, 1952 8 Sheets-Sheet 7 74675 ROTATION 65 Inventors Sidney J Finn Wa/terL.Benedict Ha nsF'Sahaefe; Jr." John W [furs/z By 2 ez'rA orney 8 Sheets-Sheet 8 FiledMarch 28, 1952 NNQ mn m w %N% wwm mmw mm gm JL 4 @R mmm w a QR .R aw H BUeied W W Q 2,740,142 MACHINES FOR OPERATING N s noEs Application March28, 1952, Serial No. 27?,4184 85 Claims. (Cl. 12 17.2)

This invention relates to machines for operating on shoes and moreparticularly to a novel machine of the type having a jack for supportingand feeding a shoe, so as to transfer a point of operation around amarginal portion of the shoe, while automatically maintaining the shoein a predetermined position, relatively to an operating device, as thepoint of operation is thus transferred around the shoe. Although hereinillustrated, by way of an example, as embodied in a machine forprogressively sewing the lasting margin of the upper of a shoe and awelt to a rib on the insole of the shoe, it will be understood that themachine of this invention is of broader utility and, therefore, adaptedfor use generally in machines for performing other operations along themarginal portions of shoes. p

In certain prior machines of the aforementioned type, it has beenproposed to locate the shoe by engagement with portions of the operatingdevice and to control certain swinging and tipping movements of thejack, which are made to position the shoe relatively to the operatingdevice, by means of so-called pattern cams, while the feeding movementsare imparted to the jack by means of a so-called feed cam as, forexample, is illutsrated in United States Letters Patent No. 1,616,714,issued February 8, 1927, in the names of Laurence E. Topham and AlfredR. Morrill. While arrangements of this type operate in a satisfactorymanner, they do involve the use of complicated, and hence costlymechanical constructions and require a number of different sets ofshoefliositioning, or pattern cams, in order to accommodate shoes thatvary in style, or when changing over from rights to lefts. Moreover,while a considerable range of sizes may be handled in machines of thistype, this is accomplished only by the use of complicated feedmechanisms and at the expense of some loss of accuracy in thepositioning of the shoe, relatively to the operating device. Althoughattempts have hitherto been made with a view to overcoming thesedifliculties, as, for example, by the use of mechanism which eliminatesthe need for certain of the so-called pattern cams, as proposed, forexample, in United States Letters Patent No. 2,005,104, issued June 18,1935, in the name of Alfred R. Morrill, theremaining pattern and feedcams restrict the flexibility and accuracy of the machine and thenecessity of guiding the shoe by engagement with portions of theoperating device is still present.

It is, therefore, an object of this invention, to provide a novel andimproved machine of the type here under consideration by means of whichthe aforementioned objections and diificulties are wholly overcome. Tothis end, and in accordance with a feature of the invention, the hereinillustrated rnachine is provided with a poweroperated jack forsupporting and feeding a shoe, to transfer the point of operation of anoperating device around a marginal portion of the shoe, which isautomatically controlled so as to locate the shoe and to maintain itin apredetermined operating po'sition,relatively to the operating device bymechanism including members for engaging contour surfaces on, or carriedby,- the shoeitself. More particularly, and in accordance with otherfeatures of the invention, the several movements of the jack, which arerequired to locate the shoe and to' maintain it in a predeterminedoperating position, relatively to the operating device, as the point ofoperation of the device is transferred around a marginal portion of theshoe; are produced by means 'of a plurality of motors which are underthe direct control of means actuated ,by shoe-engaging feelers.Preferably,- and in the herein illustrated machine, the severalaforementioned movements of the shoesupporting jack are effected bymeans of fluid-pressureoperated motors, while. the means for controllingthese motors comprises so-calle fluid jet relays which are actuateddirectly by the slide-engaging feelers. Inasmuch as contour surfaces on,or carried by the shoe being oper ated on, are utilized for controllingall of these positioning movements of the jack, this arrangement isuniversally adaptable to variations in style and size, as well asbetween rights and lefts.

With reference to an operating device, six different movements arerequired to position a shoe relativelyto the device, to feed the shoe soas to transfer the point of operation along the marginal portion 'of theshoe and to maintain a predetermined operative relation between the shoeand the operatingdevice, during the feeding of the shoe.

rectangular axes or coordinates, while the other three movements occuras rotations, respectively, about these coordinates as axes. Forconvenience in identification, these coordinates may be designated in aconventional way as x'-x, yy and z "z; while the rotation of the shoeabout these coordinates may be referred to respectively as xr, yr and21-. Thus the shoe may be positioned, relatively to the operatingdevice, by rectilinear movements along; or parallel to, two of thesecoordinates, and the feeding of the shoe may be effected by rectilinearmovernent along, or parallel to, the third coordinate. However, in orderto maintain a predetermined operative relation between the shoe "and theoperating device, as the shoe is fedalong, the shoe mus't'also berotated about each of these coordinates, or axes. Accordingly, the j'ackof the herein illustrated machine is so constructed as to provide forthe aforementioned six movements which "may, for convenience, bedenominated respectively as transverse or in and out (x-' 'x),longitudinal or feeding '(y -y), heightwise or up and down ('z-z),rotational ('zr )',1ongitudinal or pitch tipping (air) and lateral orroll tipping (yr) movements. In order that each of these movements mayoccur without displacing the shoe along, or above, other of thesecoordinates, the herein illustrated jack is so constructed that these"coordinates intersect substantially at the workin'g po'int 'of thedevice and remain in this position during all movements of the jack. Tothis end, the several slides and/or bearings along, or "about which theseveral motions take place, are supported by each other in a definitesuperimposed relation so that the transverse, longitudinal, andheightwise slides, or bearings, the supported on the rotational hearing,or slide, which in turn is mounted on the longitudinal tipping andlateral tipping slides, or bearings. v

For effecting the aforementioned movements of the jack, sixfiuid-pressure operated motors are provided and these motors arecontrolled by means of so-called fluid jet relays which, in turn, areactuated by feelers that are arranged to engage contour surfaces on theshoe itself. These feelers are adapted to respond to any departure ofthe shoe from its correct position, at-any instant, and to effect themovement, or movements, of the jack which are necessary to return theshoe to its eorrectposition.

For example, any departure of .the shoe from a correct Patented Apr. 3,1956- Three of these movements may be considered. as taking place,respectively, along, or parallel to, threeheightwise position isdetected by an appropriate feeler which, through the action of itsassociated fluid jet relay, immediately initiates movement of the jack,by the upand-down or elevation motor, in a direction to return the shoeto the desired position. Such movement, in turn, is sensed. by thefeeler which, through its fluid jet relay, brings the motor to a stopwhen the shoe reaches the desired position. Similar actions occur withrespect to all of the other movements of the jack which are required forpositioning the shoe and for maintaining it in a predetermined operativerelation to the device.

As suggested above, the transverse and longitudinal slides, or bearings,of the jack are supported on the rotational bearing, or slide. Assumingthat the point of operation is to be transferred along the marginal edgeof the bottom of a shoe on the jack, from the heelbreast line on oneside of the shoe to the heel-breast line on the opposite side of theshoe, it will be apparent that the jack will have to be rotated in ahorizontal plane and through an angle of approximately 180 in order tomaintain the marginal edge of the shoe bottom in the desired relation tothe operating device, i. e., with a line tangent to the edge of the shoebottom at the instant point of operation parallel to the directioninwhich the shoe must be fed along, relatively to the operating device,and perpendicular to the direction in which the shoe must be moved,toward or away from the operating device, to position the Working pointtransversely, with respect to the operating device. Accordingly, thefeeding of the shoe and also its transverse movements toward or awayfrom the operating device must he etfected by combinations of movementsof the jack along its transverse and longitudinal hearings, or slides,and only at certain points along the marginal edge of the shoe bottomwill the feeding and/ or lateral movements of the jack correspond, or beparallel to, the movement of the jack along these slides or bearings. Onthe other hand, however, the movements of the shoe-engaging feeler,which, by controlling the operation of the fluid-pressure-operatedmotors, efiect the feeding and lateral correcting movements of the jack,do take place in directions corresponding respectively, to the directionof feed of the shoe and to the direction of lateral or transversemovement of the shoe, toward or away from the device.

In order that such movements of these feelers may effeet the desiredfeeding and transverse correcting movements of the shoe, by combinedmovements of the jack on its longitudinal and transverse bearings, thefollowing arrangement is provided, in accordance with a feature of theinvention. The movements of the jack along its longitudinal bearing andalong its transverse hearing are controlled by a combined fluid jetrelay having a single jet nozzle, which is mounted for universalmovement in a plane parallel to two of the rectilinear coordinatesmentioned above (x--x, y-y), and a jet receiver having four openingsarranged in equi-angular relation. Two oppositely disposed of these fouropenings are connected, respectively, to the opposite ends of afluid-pressureoperated motor adapted to efiect movement of the jackalong its longitudinal slide, or hearing, while the other two oppositelydisposed openings are connected respectively, to the opposite ends of afluid-pressure-operated motor adapted to effect movement of the jackalong its transverse slides, or bearings. This jet receiver is mountedfor rotation and is operatively connected to the jack in such a waythat, as the jack is rotated around its rotary slide, or hearing (zr)the first-mentioned pair of oppositely disposed openings are always inalinement with the direction of movement of the jack along itslongitudinal slide, or hearing, while the last-mentioned pair ofopenings are always in alinement with the direction of movement of thejack along its transverse slides, or bearings.

With this arrangement, a displacement of the jet nozzle of this fluidjet relay in any direction will result in movement of the jack inexactly the opposite direction.

4. The feeler for controlling the transverse (in-out) position of theshoe relatively to the operating device, to displace the jet nozzle in adirection parallel to the x-x coordinate, mentioned above, while themechanism for effecting the feeding of the shoe, to be referred tobelow, is arranged to displace this same jet nozzle in a directionparallel to the y-y coordinate. Therefore, re-

gardless of the angular (2r) disposition of the jack, the

desired transverse correcting (x-x) andfeeding (y-y) movements will beimparted to the jack as a result of a combination of movements of thejack along its transverse and vertical line or longitudinal slides orhearings, in response to corresponding displacements of the jet nozzle.

Preferably, and as herein illustrated, the feeler which controls thetransverse in-out positioning movements of the jack is so arranged thatits contacting point is coincident with, and displaceable in a directionalong, the x-x coordinate of movement of the jack, while the operatingpoint of the feeler which controls the rotational (Zr) movements of thejack is ofiset somewhat from the first-mentioned feeler in a directionparallel to the direction of feed of the shoe. As will be apparent, acorrecting movement of tire shoe, toward or away from the operatingdevice, effected by displacement of the inout feeler, would tend toproduce a corresponding displacement of the rotation feeler which wouldresult in an undesired rotational movement of the shoe. In order toovercome this difliculty and assure that the rotation feeler will effectonly the desired rotational movements of the shoe, regardless ofdisplacement of the in-out feeler, the following arrangement isprovided, in accordance with a further feature of the invention. Therotational feeler is pivoted on an arm which has a fixed pivot point andis connected directly to the in-out feeler. Thus the rotational feeleris mounted for movement toward and away from the shoe, with the in-outfeeler, without displacement of the jet nozzle of its associated jetrelay, and responds only to displacements relatively to the inout feelerwhich result froma change in the curvature of the contour surface.

In the herein illustrated machine, the feeding movements of the jack areprovided by a combination of the movements of the jack along itstransverse and longitudinal slides, or hearings, and these movements areeffected as a result of displacement of the jet nozzle of the combinedfluid jet relay, referred to above, in a direction parallel to the yycoordinate. The arrange ment of this combined jet relay is such that thelinear rate of feeding movement of the jack is proportional to theextent of displacement cordauce with another feature of the invention,means are provided for matching the rate of feed of the shoe by the jackto the normal rate of feed of the shoe by the operating device. Moreparticularly, the invention is illustrated as embodied in a machine forprogressively sewing the upper and welt of a lasted shoe to a rib on theinsole of the shoe. Thus this machine has an in seaming head ofconventional construction which is provided with an awl for piercing thewelt, upper and insole rib, a needle for entering the hole thus formed,and the usual stitch-forming devices, cooperating with the needle toform a seam for progressively securing the welt and upper to the insolerib. As is common in inseaming heads of this type, the awl and needleare adapted, while penetrating the welt, upper and insole rib, to imparta substantially continuous feeding movement to the jack. However, theinseaming head may have other types of shoe-engaging means for impartinga feeding movement to the shoe such, for example, as are disclosed inthe patent to Topham et al. No. l-,6l6,7l4, referred to above. It is,therefore, necessary that the rate of feeding movement of the jack bematched to the rate of feeding movement imparted to the shoe by the awland needle, or other shoe-engaging means. For

is adapted.

of its nozzle and, in acamaze the herein illustrated niachinefisprovidedwith mechanism, associated "with the c'a'in shaft er the inseaming headand op'eratively connected to the jet nozzle of the 'combinedlluid jetrelay, which is adapted the rate of feed of the shoe by feeding'rate ofthe awl and neeby displacement of the jet nozzle in accordance vary thefeeding rate of the jack until it exactlym'atches the normal feedingrate of the inseaming head. More particularly, the rate of feed of thewelt, as it travels along during the inseaming'operation, is used as ameasure of the rate of feed of the jack and this a is varied, bydisplacement of the aforementioned jet exactly matched to the rate ofthe feed head.

In automatic machines of the type herein under consideration, it isessential, if full advantage of the time and labor-saving possibilitiesare to be realized, that the loading and unloading of shoes be readilyaccomplished with a minimum amount of operator skill and effort. It is,therefore, another object of this invention, to provide a novel andimproved apparatus for handling shoes which greatly facilitates theloading and unloading of the jack of the herein illustrated machine. Forthis purpose, the jack of the machine is adapted to receive and hold anyone of a plurality of shoe holders on which the shoes to be inseamed canbe mounted by the operator, during the automatic operating cycle of themachine. In order that the automatic operation performed by the machine,herein illustrated as inseam ing, may certainly be commenced andterminated at appropriate locations along the marginal portion of everyshoe, the jack is arranged to receive and hold each successive shoeholder in the same relative position, when placed thereon by anoperator, and supplementary means are provided for locating eachsuccessive shoe on its holder in a predetermined position.

In order to facilitate the loading of shoes mounted on shoe holders ontothe jack, and their subsequent removal therefrom after inseaming, and torelieve the operator of the responsibility for starting and stopping theoperation of the jack and of the operating device, the hereinillustrated machine is, in accordance with still further features of theinvention, provided with auxiliary, or secondary controlling mechanisms.More particularly, these controlling mechanisms include electricallyoperated valves for controllling various movements of the jack and anelectrical system for controlling the operation of these valves. Thus,the arrangement is such that, after a shoe holder and shoe have beenloaded onto the jack, this controlling mechanism is effective, inresponse to the closing of a starting switch by the operator, first ofthe inseaming initiate the automatic feeding and positioning movementsof the jack and to start the action of the operating device, and finallyto terminate the automatic feeding and positioning movements of the jackand the action of the operating device and to cause the jack to returnto its loading position. In addition, this secondary controllingmechanism includes certain safety devices adapted to terminate theautomatic operating cycle of the jack and operating device immediatelyin; response to faulty action of. either the jack or the operatingdevice, or at the will of the operator.

7 means of -a belt 58,- Fig; 1.

and other objects and feait ures o f the invention wil, appe'eir'in the,following detailed description of a preferredembodimentthereofillustrated in the accompanying drawings and will bepointed out in the claims.

In the drawings, 7

Fig. lis a perspective view of the 'front of a machine embodying thefeatures of this invention; 7 H

Fig. 2 is a view 'in front elevation of a loading station which isassociated with the machine shown in Fig. 1

Fig. 3 is a view in end elevation of a portion of the loading stationshown 'in Fig. 2; I

i Fig. 4 is a view in vertical section substantially on line IV-IV ofFig. 2 and looking in the direction of the arrows, of a portion of ashoefholder which is shown mounted onth'e loadingstation in Fig. 2;,

Fig. 5 is a plan view of the shoe holder with certain parts broken awayand others shown in section;

Fig. 6 is a plan view of a portion of the machine shown in Fig. l withcertain parts broken away and others shown in section; I v

Fig. 7 is a view in front elevation ofafeed-controlling mechanismforming a part of the machine illustrated in Fig. 8 is a detail view ofa portion of the machine with certain partsin verticalsection;

Fig. 9 is a perspective exploded view, atan enlarged scale, of certainelements of that portion of the machine which is shown in Fig. 8;

Fig. 10 is a schematic perspective view of a tion of the machineillustrated in Fig. 1; i

Fig. 11 is a plan view of shoe-e'ngaging feelers forming part of thecontrolling mechanism of the machine; I

Fig. 12 is a perspective view of the operating and controlling elementsof the machine together with a portion of a shoe being operated upon;

Fig. 13 is a hydraulic diagram; and

Fig. 14 is an electrical diagram.

Referring to these drawings, and particularly to Figs. 1 and 10 thereof,the machine illustrated therein is adapted major porposition, relativelyto 7 Thus, the machine is provided with an inseammg head of knownconstruction which is indicated generally by an awl 42, I finger 46, awelt guide 48 and a thread take-up, not shown. I These several operatinginstrumentalities are associated with a' head casting 50, Figs. 1 and 6,and are operated by means of a driving and stopping mechanism, containedwithin this head casting and including a main ca'in shaft 52partiallyillustrated in Fig. 6, and a control clutch, not shown.

I Mounted on the top of: the head casting 50 is a thread supplycontainer 60 from which see the thread '1 is directed downwardly intothe head casting, Where it is engaged with the thread take-up mechanism,not shown, and thence to the looper 44 and other operatinginstrumentalities. Because of the manner in which the shoe beinginseamed is automatically fed along and positioned, with respect to theoperating instrurnentalities of the inseaming head, by means of the jackand the control mechanism to be described below, in the inseaming headherein illustrated the usual back rest {see element of the machineillustrated in the firstrnentioned Morrill patent, referred to above)has been omitted, while the function of the channel guide (element 18 ofMorrill) is performed by another element of the herein illustratedmachine in a manner which will appear below. In all other respects,however, the inseaming head operates to sew the upper U of a shoe S anda welt W to the rib R of the insole I of the shoe in exactly the samemanner as is explained in the first-mentioned patent to Merrill to whichreference may be had for details not here described. In addition to theoperating instrumentalities mentioned above, the inseaming head hereinillustrated is provided with a thread-gripping member 70, a welt knife72, a thread knife 74 and a weltadvancing finger 76, see Fig. 12. Theseelements correspond, respectively, with the elements 736, 864, 866 and884 of the machine disclosed in the secondmentioned Morrill patent andoperate in the manner explained in that patent when the inseaming headis caused to go through its so-called back-up cycle.

The shoe-supporting and feeding jack 22 is illustrated in Fig. 1 and isalso shown, more or less schematically, in Fig. 10 of the drawings. Thisjack comprises an upper work-supporting member 100 which, as will beexplained below, is adapted to receive a shoe holder, indicatedgenerally by the reference character 102. This work-supporting member iscarried on the upper end of a piston 104, which is slidable in acylinder 106. This cylinder extends upwardly from a cross slide 108which is supported for reciprocating movement on a second cross slide110 and this second slide is supported for reciprocating movement on atable 112. This table is rotatably mounted in a bearing 114-, carried byan arcuate slide 116 which is supported for movement in guideways 118formed in the upper part of a second arcuate slide 120. The arcuateslide 120, in turn, is mounted for arcuate movement in guideways 122,formed in a base member 124 which is secured to the base portion 24 ofthe frame construction. The cross slides 108 and 110 are constrained forreciprocating movement at right angles to each other, while the arcuatemovements of the slides 116 and 120. are confined to planesperpendicular to each other. The centers of curvature of the two sets ofguideways 118 and 122 min cide at, or substantially at, the so-calledpoint of operation of the operating instrumentalities of the inseaminghead. The axis of rotation of the table 112 passes through this point ofoperation and thus includes the centers of curvature of the guideways118, 122. Accordingly, the construction of this jack is such that, byvarious combinations of movements of the several slides, a shoe Smounted on a shoe holder 102, received in the supporting member 100, canbe fed along, to cause the point of operation of the inseaming head tobe transferred around a marginal portion of the shoe while the shoe ismaintained in a predetermined operating position, relatively to theoperating instrumentalities. As has already been suggested above, forthus feeding the shoe and maintaining it in a predetermined operatingposition, six movements thereof are required, namely, rectilinearmovements parallel to three rectangular coordinates xx, y-y and zz, androtary movements about these axes, i. e., xr, yr and zr, see Figs. 10and 12. For convenience, these six movements will be referred to below,respectively, as transverse, feeding, vertical, pitch, roll androtation.

Referring to Fig.12, the shoe S is positioned laterally,

with respect to the operating instrumentalities of the inseaming head,by transverse movements in directions parallel to the coordinate x-x, itis located in a heightwise direction by vertical movements in directionsparallel to the coordinate z-z, the bottom of the shoe, at the instantpoint of operation, is leveled longitudinally, and laterally,respectively, by rotation about the coordinate x-x (pitch) and about theaxis yy (roll), and a line tangent to the marginal point of the shoe, atthe operating point, is maintained in a position substantiallyperpendicular to the line of action of the awl 42 and needle 40, byrotation about the coordinate zz, while the feeding of the shoe totransfer the point of operation along the marginal portion of the shoe,i. e., insole rib R, is effected by movement of the shoe in a directionparallel to the coordinate y-y. As will be apparent, these severalmovements correspond to those which would be imparted to the shoe by anoperator for feeding the shoe while maintaining it in a proper position,relatively to an operating device, such for example as an inseaminghead.

The several positioning movements of the shoe, referred to above, areeffected as a result of individual and/or combined movements of theseveral component parts of the jack which are produced by power-operatedmeans and controlled by shoe-engaging feelers. Referring particularly toFig. 10, the vertical movements are imparted to the shoe by means of thepiston 104 in response to fluid under pressure, admitted to, orexhausted from, the opposite ends of the cylinder 106 through a pair ofconduits 140, 142, see also Fig. 13. The transverse move ments and thelongitudinal, or feeding, movements are imparted to the shoe as a resultof reciprocation of one or the other, or both of the cross slides 108,110. For thus reciprocating the cross slide 108 there is connected to ita double piston arrangement 144 which operates in a double cylinderconstruction 146, and connected to the opposite ends of the doublecylinder 146 are a pair of conduits 148, 150. Similarly, reciprocatingmovements are imparted to the cross slide by means of a double piston152 which operates in a double cylinder 154. This double piston isconnected to the slide 110 by means of rack teeth 156, pinions 158, 160and rack teeth 162, which are cut on this slide, Fig. 10. Connected tothe opposite ends of the double cylinder 154 are a pair of conduits 164,166. Rotation of the table 112 is effected by means of a rotaryfluid-pressure motor 168 which drives a pinion 169 meshing with a gear170, associated with this table. Leading from the opposite sides of themotor 168 are a pair of conduits 172, 174. Arcuate movement of the slide116 is effected by means of a double piston 176 which is received in adouble cylinder 178 and connected to the slide by means of rack teeth180, pinions 182, 184 and rack teeth 186 on this slide. Leading from theopposite ends of the cylinder 178 are a pair of conduits 1'88, 190.Similarly, arcuate movement is imparted to the slide by means of adouble piston 192 which is received in a double cylinder 194 andoperatively connected to this 196, pinions 198, 200 and rack teeth 202on this slide. Leading from the opposite ends of the cylinder 194 are apair of conduits 204, 206.

The flow of pressure fluid to, and exhaust from, the several pairs ofconduits 140, 142; 148, 164, 166; 172, 174;,188, and 204, 206 foreffecting vertical movement of the piston 104, reciprocating movementsof the cross slides 108, 110, the rotation of the table 112, and thereciprocating movements of the arcuate slides 116, 120 are controlled,respectively, by six fluid jet relays of the type disclosed in UnitedStates Letters Patent No. 2,672,150, issued March 16, 1954, in the namesof Walter L. Benedict and Sidney J. Finn. As is explained in more detailin the mentioned Benedict et al. patent, jet relays of this type includea movable jet nozzle for controlling the flow of pressure fluid from asuitable source to, and

slide 'by means of rack teeth exhaust from, a pair of openings in a jetreceiver, the arrangement being such that extremely small displacementsof the jet nozzle, from a centered position relatively to the twoopenings, results in relatively large pressure diiferences in dischargeconduits connected to the two openings so that an extremely sensitiveand accurate control of the operation of a fluid-pressure motor, towhich the discharge conduits are connected, is provided.

The jet relay which controls the operation of the piston 104 isindicated generally by the reference character 210, and comprises amovable jet nozzle 212, and a jet receiver 214 having a pair of openingswhich are connected respectively to the conduits 140, 142, see Fig. 10.For displacing the jet nozzle 212 from a centered position with respectto the openings in the jet receiver 214, thereby to control the verticalreciprocating movements of the piston 104, this nozzle is connected toone arm 216 of a double-acting feeler 218 by means of a link 220, Figs.and 11. This feeler has an operating end which, during the operation ofthe machine, is adapted to engage the bottom of the insole I of the shoeS and the inside face of the insole rib R, see Figs. 11 and 12, and issupported on a horizontal shaft 222 by means of a universal joint,including a vertically disposed shaft 224, in such a manner that itsoperating end is free to move in two directions, one generally parallelto the coordinate zz and the other generally parallel to coordinate x-x.As illustrated diagrammatically in Fig. 11, the feeler 218 is constantlybiased in directions toward engagement with the bottom of the shoe andwith the inside surface of the insole rib by means of coil springs 224,226. Movement of this feeler in a direction parallel to the coordinatez.z, i. e., in a heightwise direction, will rock the arm 216 about theaxis of the shaft 222 and shift the link 220 in a directionsubstantially parallel to its length, thereby displacing the jet nozzle212 of the relay 210. As is explained in the Benedict et al. patent,this jet nozzle is normally held in a centered position, relatively tothe openings in the jet receiver 214, and when in this position, thepressure of the fluid in the conduits 140, 142 is equalized and thepiston 104 is held stationary. Hence, vertical displacement of thefeeler 218 will shift the nozzle from centered position and result in acorresponding vertical movement of the piston 104. The arrangement issuch that, when this feeler is moved upwardly, the piston 104 will bemoved downwardly and vice versa. It will, therefore, be apparent thatthe piston 104, jet relay 210, link 220, and feeler 218 will function asa closed loop servo mechanism which will effect vertical movements ofthe shoe S so as to maintain the point of operation, adjacent to thelocation where this feeler engages the bottom of the insole I, in apredetermined heightwise position, relatively to the operatinginstrumentalities of the inseaming head, as the thereof is provided withtwo sets of openings 242, 242 and 244, 244, see Fig. 9, and is mountedfor rotation in a bearing block 246, Fig. 8. The openings 242, 242 aredisposed along a horizontal axis zza while the openings 244, 244 aredisposed along horizontal axes yy at right angles thereto. The jetreceiver is formed as a block 248 which is provided with two pair ofannular groovesv 250, 250 and 252,

252 These pairs of grooves are connected,

. 10 respectively, to the openings 242, 242 and 244', 244 by pairs ofaxial passages 254, 254 and 256, 256, and also to the conduits 148, 150and1-64, 166, see Figs, 8 and 9. The block 248 has an integrally formedshaft portion 258 and secured to this shaft portion is a worm wheel 260.This worm wheel is in mesh with a worm 262, Fig. 8, which is connectedto one end of a flexible shaft 264. Secured to the other end of thisflexible shaft is a pinion 266 which is in mesh with the gear 170 on thetable 12. The ratios of the gears 266, 170 and worm and wheel 260, 262are such that the jet receiver 240 is revolved in unison with the table112 and hence remain in a predetermined orientation relatively to thetwo cross slides 108, 110 which are carried by this table. Referring toFigs. 9, 10' and 11, the orientation of the jet receiver 240 is suchthat, as the table 112 is rotated, the line a-a, along which theopenings 242, 242 are disposed, Fig. 9, always remains parallel to thedirection of movement of the cross slide 108, while the line bb, alongwhich the openings 244, 244 are disposed, always remains parallel to thedirection of move ment of the cross slide 110.

The jet nozzle 236 flexible et pipe 270 which, in

244, by means of two sets of leaf springs 272, 274, Fig. 6, and when thenozzle is in this centered position its discharge orifice 276, which arealso arranged, in the manner explained in the Benedict et a1; patent, insuch a manner that the jet nozzle to a second link 280, also connectedto this nozzle. will be apparent from Fig. 6 that the arm 230 is sodisposed angularly,

direction of movement of the link 232, and also of the jet nozzle 236,in response to displacement of the feeler 218 in a horizontal directionparallel to the coordinate x-x. Accordingly, horizontal displacement ofthe feeler 218 will now cause 11 0 parallel to the coordinate x-x andthe connections between the openings244, ends of the cylinder 154 aresuch that displacement of the feeler in one direction will effectmovement of this cross slide in the opposite direction. As will be apparent, for all other orientations of the table 112 and of the crossslides 108, carried thereby, a displacement of. thefeeler 218, in. a,horizontal direction parallel to, the coordinate x.-x, will result. ina'movement of a shoe mounted on the supporting member 100 of the jack inthe opposite direction, as a result of a combination of movements of thecross slides 108, 110. Thus, the feeler 218, link 232, jet nozzle 236,jet receiver 240, and the pistons and cylinders 144, 146 and 152, 154associated with the cross slides 108, 110 provide a closed loop servomechanism which will effect transverse movement of a shoe S in adirection parallel to the coordinate x--x, to maintain the point ofoperation adjacent to the location in which the feeler 218 engages theinside of the insole rib R, in a predetermined position laterally of thebottom of the shoe, relatively to the operating instrumentalities of theinseaming head, as the shoe is fed along to transfer the point ofoperation along the marginal portion of the shoe bottom.

Referring again to the jet nozzle 236, as was explained above, thisnozzle is constrained by the leaf springs 272 and 274 for movement inone or two paths at right angles to each other, one of which path isparallel to the direction of movement of the link 232, while the otheris parallel to the direction of movement of a second link 280. It hasalso been pointed out that movements of this jet nozzle along the firstof these two paths, as a result of displacement of the feeler 218 in ahorizontal plane and substantially parallel to the coordinate x-x,effects transverse movement of the shoe S, relatively to the inseaminghead, by individual or combined movements of the cross slides 108, 110.It, therefore, should be apparent from the geometry of the setup, thatdisplacement of the jet nozzle 236 along the second path, by movement ofthe link 280, will result in movement of the shoe in a directionparallel to the coordinate yy, i. e., a feeding of the shoe to transferthe point of operation of the inseaming instrumentalities along themarginal portion of the bottom of the shoe. Thus, as will appear below,the operation of the jack to feed the shoe is controlled by mechanismwhich acts through the link 280 is displace the jet nozzle 236 along thelast-mentioned path and in a direction at right angles to the directionin which this nozzle is displaced by movement of the feeler parallel tothe x-x coordinate.

As the shoe is fed along by the jack, it is moved transversely andvertically by the two closed loop servo mechanisms which are controlledby the feeler 218 and thus the point of operation, adjacent to thisfeeler, is maintained in the proper heightwise and lateral positions,transversely of the inseaming head. In addition to these transverse andheightwise positioning movements of the shoe, which take place parallelto the x-x and z-z coordinates, it is necessary that the shoe be rotatedabout the coordinate z-z, in order to maintain the tangent to themarginal portion of the shoe, at the instant point of operation,substantially parallel to the y-y coordinate, and normal to the line ofaction of the: operating instrumentalities, and also that the shoe berotated about one or both of the coordinates xx and yy so that thebottom of the shoe, adjacent to the point of operation, is maintained ina position substantially parallel to the line of action of the operatinginstrumentalities, i. e., is leveled. The first of these movements willbe referred to as rotation, while the other two motions are identi fied,respectively, as pitch (rotation about the x-x coordinate) and roll(rotation about the yy coordinate).

The rotation movements of the shoe are controlled by the conjoint actionof the feeler 218, previously mentioned, and another feeler 300, Figs.10, 11 and 12. As is shown in Fig. 11, the feeler 300 has an operatingend which is adapted to bear against the bottom of the insole I of theshoe S and against the inside surface of the insole rib R. This feelerhas two arms 302 and 304 and is mounted for pivotal movement, in a planegenerally perpendicular to the x--x coordinate, on a shaft 306, and forpivotal movement also in a plane substantially perpendicular to the z--zcoordinate, on a universal joint'including a pin 308. Supported on thearm 304 of this feeler, by means of a flexure point comprising a thinstrip of metal 310, is a bell-crank lever 312 one arm 314 of which isconnected, by means of a link 316, to the arm 230 of the feeler 218.With this arrangement, if the operating end of the feeler 300 isdisplaced in either direction, in a plane parallel to the x-x and y-ycoordinates and relatively to the feeler 218, the link 316 and thebell-crank lever 312 will pivot about the point of connection of thelink 316 to the arm 230 and the other arm 318 of the bell-crank lever312 will be displaced in the opposite direction as the operating end ofthe feeler. However, if the operating ends of both of the feelers 218and 300 are displaced equally, in. either direction in a plane parallelto the x-x and y-y coordinates, the end of the arm 318 of the bell-cranklever 312 will remain stationary as the swinging movement of the arm 304is equalized by an equal and opposite swinging movement of thebell-crank lever 312,

about the flexible joint, imported to it by the link 316.

Thus, if the shoe S assumes a position in which the tangent to themarginal portion at the point of operation, i. e., a line drawn betweenthe points of contact of the feelers 218, 300 with the inside of theinsole rib R, is not parallel to the y-y coordinate, the end of the arm318 of the bell-crank lever 312 will be displaced from the position inwhich it is shown in Fig. 11. Connected to the outer end of the arm 318of the bell-crank lever 312 is one end of a link 320 the other end ofwhich is connected to the movable jet nozzle 322 of a jet relayindicated generally by the reference character 324, see Fig. 10. Thisjet relay is similar to those previously mentioned and has a jetreceiver 326 provided with two openings which are connected,respectively, to the two conduits 172, 174 leading to the opposite endsof the rotary fiuid pressure motor 168. As has been previouslyexplained, this motor is adapted to rotate the table 112 and thearrangement is such that, when the feeler 300 is displaced in eitherdirection, relatively to the feeler 218, as a result of the shoe Sassuming a position in which a line between the points of contact of thefeelers 218, 300 with the insole rib R is not parallel to the coordinatey-y, the motor 168 will be caused to rotate the table 112 and the shoe 8which is supported thereon in the opposite direction until the shoeassumes the desired position with the line of contact of these feelerswith the rib substantially parallel to the yy coordinate. The feeler 300is constantly biased in a direction toward the rib R by means of aspring 332, diagrammatically illustrated in Fig. 11. Hence, as the jackis operated to effect feeding of the shoe, to transfer the point ofoperation along the marginal portion of the shoe, the feeler 300 willconstantly engage the inside surface of the insole rib R and, as aresult of displacement relatively to the feeler 218 in a plane parallelto the x-x, y-y coordinates, effect rotation of the table 112 and alsoof the shoe S in a proper direction to maintain the tangent to themarginal portion of the shoe at the instant point of operation,substantially parallel to the yy coordinate.

The arm 302 of the feeler 300 is connected, by means of a link 340, tothe movable jet pipe 342 of a jet relay indicated generally by thereference character 344. This jet relay is similar to the otherspreviously described and has a jet receiver 346 which is provided with apair of openings connected, respectively, to the two conduits 188, whichlead to the opposite ends of the cylinder 178. A spring 352,diagrammatically illustrated in Fig. 11, is adapted to swing the arm302, by rotation about the axis of the shaft 306, in a direction to movethe feeler 300 downwardly and into engagement with the bottom surface ofthe insole I of the shoe S. The arrangement is such that, when the jetpipe 342 is displaced from its centered position, as a result ofmovement of the feeler 300 in either direction about the shaft 306 as anaxis, the shoe S will be rocked in a direction to return the jet pipe toits centered position, in response to arcuate movement of the slide 116by the piston 176. Also mounted for pivotal movement on the shaft 306 isa third feeler 368 having an operating end and an arm 362. This arm isconnected, by means of a link 364, to the movable jet pipe 366 of a jetrelay, indicated generally by the reference character 368. This jetrelay is similar to those already described and has a jet receiver 370provided with a pair of openings connected, respectively, to the twoconduits 204, 2% which lead to the opposite ends of the cylinder 194. Aspring 376, diagrammatically illustrated in Fig. 11, is adapted to swingthe arm 362, by rotation about the axis of the shaft 306, in a directionto move the feeler 360 downwardly and into engagement with the bottomsurface of the insole I of the shoe S. The arrangement is such that,when the jet pipe 366 is displaced from its centered position, as aresult of swinging movement of the feeler 360 in either direction, theshoe S will be rocked in a direction to return the jet nozzle to itscentered position, in response to arcuate movement of the slide 129 bythe piston 192.

The arcuate movements of the slide 116 take place in a plane which isperpendicular to the x-x coordinate and the radius of curvature of thisslide is such that its center is on the xx coordinate, while the arcuatemovements of the slide 120 take place in a plane Which is perpendicularto the yy coordinate and the radius of curvature of this slide is suchthat its center is on the yy coordinate. As shown in Figs. 11 and 12,the point of contact of feeler 300 with the bottom of the insole I liessubstantially on the yy coordinate, while the point of contact of thefeeler 360 lies on the xx coordinate. Also, the feeler 218 engages theinsole I at the point of intersection of these two coordinates, i. e.,on the coordinate z-z. Accordingly, as the jack is operated to feed theshoe S to transfer the point of operation of the inseaming head alongthe marginal portion of the bottom e., is leveled, as a result movementsof the shoe about the x-x coordinate (pitch) and y-y coordinate (roll)by the pistons 176 and 192 in response to displacement of the jetnozzles 342, 366 by the feelers 300 and 366.

As has been pointed out above, the longitudinal feeding movements of theshoe, to transfer the point of operation along the marginal portion ofthe bottom of the shoe, are effected by a combination mounted on abearing stud 422 formed on the housing 410, and this idler gear is inmesh with a bevel gear 424 on the end of the cam shaft 52 of theinseaming head, see Fig. 6. The shaft 414 extends somewhat beyond theend of the bearing extension 412 and slidably supported on thisextending portion of the shaft is a carrier member 426 in which there isjournaled a shaft 428. Secured to this shaft, within the carrier whichis hollow, is a Worm wheel 430 and fast on this shaft outside of thecarrier is a roller 432. A leaf spring 434, secured at its opposite endsrespectively to an arm 436, which extends forwardly from the lowerpartofthe bearing extension 41 2',- and an arm 438, which is fastened to thecarrier- 426,"

normally urges the carrier to the right, as viewed in Fig. 7, and intocontact with. the end of the bearing extension 412. Pivotally mounted onthe bearing extension, by

means of a pin. 44-0, is a bell-crank lever 442 on one arm of whichthere is journaled an idle roller 444. A coil spring 446, stretchedbetween the other arm of thebellcrank lever 442 and a pin 443, on thearm 436, tends to swing the idle roller toward the roller 432 on thecarrier at one end, a leaf spring 464. engaging the lever 400 and is soarranged as to exert a force on the link 408 tending to hold the carrier426, to which one end of this link is adjustably secured, in theposition in which it is shown in Fig. 7, i. e., in engagement with theend of the bearing extension 41-2. Associated with the arm 462 is anadjusting screw 466 which bears against the extension 460. By rotatingthis screw, the arm 462 may be swung in one direction or the other tovary the action of the leaf spring 464.

The welt W which is being sewed to the insole rib R of the insole I onthe shoe As will be understood from the aforementioned Morrill patent,when the inseaming head is operating, the needle 40 and the awl 42 areadapted to impart a substantially continuous feeding movement to theshoe S and also to the welt W. As previously explained, the displacementof the jet nozzle 236 by the link 280 will cause the jack to impart afeeding movement to a shoe S mounted on the supporting member 100.Referring to Fig. 6, the arrangement is such that, when this jet nozzleis displaced by the link 280 in a direction extending downwardly and tothe left, the shoe will be fed along, from left to right, in a directionparallel to the y-y coordinate, Fig. 11, and at a rate depending on themagnitude of the displacement of the nozzle. By suitable adjustment ofthe link 408 relatively to the carrier 426, the jet nozzle 236 is causedto occupy a centered position, relatively to the two sets of openings242, 242 and 244, 244 in the receiver block 240, when the carrier 426 isin engagement with the bearing extension 412. Hence, just as soon as theinseaming head is set into operation, the shaft 414 will begin to rotatein the direction indicated by the arrow on roll 432 in Fig. 7. Rotationof this shaft in this di-" rection will tend to rotate the roller 432 ina clockwise direction, as indicated by the arrow. Inasmuch as the shoe Sand welt W are at this time stationary, this roller is held againstrotation and acts as a nut so that thecarrier 426 is shifted over to theleft, Fig. 7, by the worm 416 acting as a screw. Such movement of thecarrier immediately displaces the jet nozzle 236 from its centeredposition and the jack begins to feed the shoe and to draw along the weltW. As the welt is thus drawn along by the moving shoe, rotation of theroller 432, in the direction of the arrow in Fig. 7, is permitted, and,if the rate of feed of the shoe exceeds a predeter mined value, thisroller will actually be driven by the Accordingly, the carrier 426 willjusted toa position in which the rate be quickly ad'- of feed of theshoe is such that the moving welt tends to rotate the roller 432 atexactly the same number of revolutions per minute as the worm 416 tendsto rotate the worm wheel 430. As will be apparent, by suitably selectingthe gears 418, 420, 424, worm 416 and worm wheel 430 and the diameter ofthe roller 432, the rate of feed of the shoe by the jack can be exactlymatched to the rate of feed which would otherwise be imparted to theshoe by the awl and needle of the inseaming head.

The fluid-pressure system, by means of which fluid under pressure, e.g., oil, is supplied to the several jet relays 210, 238, 324, 344 and368, as well as to other fluid-pressure-operated mechanisms of themachine, is illustrated diagrammatically in Fig. 13. A motor-driven pump500 draws the operating fluid from a sump, not shown, and delivers itinto high-pressure feed lines 504 and 506. The line 504 leads directlyto a sequence valve 508 and has a branch line 510 which is connected toa pilot valve 512. Leading from the sequence valve are five supply lines514, 516, 518, 520 and 521 which lead, respectively, to the jet relays210, 238, 324, 344 and 368. These five jet relays are provided,respectively, with discharge pipes 522, 524, 526, 528 and 530 which leadback to the sump. The pump, together with its drive motor and the sump,the sequence valve 508 and pilot valve 512 are mounted on the frameconstruction, in back of the wall 32, as are also various other controlvalves to be mentioned below. The five jet relays are contained within apair of hollow housings, mounted on the outer ends of two hollow armswhich are supported on the shelf of the frame construction. One of thesehousings, already identified by the reference character 406, isassociated with an arm 532, while the other housing 534 is associatedwith a similar arm 536.

As will be seen in Fig. 1, the jet relays 210 and 238 are located in thehousing 406, while the jet relays 344 and 368 are located in the housing534. Also located in the last mentioned housing is the jet relay 324,which, however, is not visible in Fig. 1. The exhausting fluid from theseveral jet relays actually drains from the housings 406, 534 into thearms 532, 536 and thence back to the sump and the discharge lines 522,524, 526, 528 and 530 have been used in Fig. 13 to illustrate thisdiagrammatically.

In order to stabilize the actions of the five closed loop servomechanisms which, as has been explained above, function to position theshoe relatively to the operating instrumentalities of the inseaminghead, and also the servo mechanism which effects feeding of the shoe,there is associated with each of the pairs of conduits leading to thesix fluid-pressure-operated motors which elfect the six movements of theshoe, a stabilizing device similar to that disclosed in United StatesLetters Patent No. 2,696,804, granted December 14, 1954, in the name ofDelvin E. Kendall, J r. As is explained more particularly in the Kendallpatent, each of these stabilizing devices comprises a bypass line,extending between the two conduits, in which there are interposed aflexible diaphragm and a restricted passageway. These six stabilizingdevices are indicated generally by the reference characters 540, 542,544, 546, 548 and 550, in Figs. 1 and 10, see also Fig. 6.

In addition to the jet relays 210, 238, 324, 344 and 368, which controlthe operation of the six fluid-pressure-operated motors associated withthe jack, during the operation of the machine, the machine is alsoprovided with a plurality of auxiliary valves and an electrical controlsystem for operating the jack to effect presentation of a shoe thereonto the operating instrumentalities of the inseaming head, to initiatethe inseaming operation and to bring it to a stop, and to withdraw theshoe from the operating instrumentalities to a convenient location forthe removal of the inseamed shoe and the loading of another shoe. Thus,in addition to;thesequence valve 508 and its associated pilot valve512,- which have already been mentioned, ,the fluid-pressure system alsoincludes a longitudinal feed shut-off valve 560 and an auxiliarylongitudinal feed valve 562 which are associated with the conduits 164,166 leading from the jet relay 238 to the opposite ends of the cylinder154; a jet reversing valve 564, which is associated with the conduits148, 150, leading from the jet relay 238 to the opposite ends of thecylinders 146, and also with the conduits 140, 142 leading from the jetrelay 210 to the opposite ends of the cylinder 106; an auxiliarytransverse feed valve 566 and a rotation shut-off valve 568, which isassociated with the supply line 518 which leads from the sequence valveto the jet relay 324, see Fig. 13.

The longitudinal feed shut-01f valve 560 has a plunger 600 which isurged to the position shown in Fig. 13 by means of a coil spring 602,thereby shutting off the conduits 164, 166 which lead to the oppositeends of the cylinder 154. Connected to this valve plunger is thearmature 604 of a valve-operating solenoid 606, having a coil 608. Whenthis solenoid is energized, the valve plunger 600 will be shifted overto the left, Fig. 13, thereby opening the conduits 164, 166. Theauxiliary longitudinal feed valve 562 has a plunger 610 which isnormally held in the centered position by means of a spring-operatedcentering plunger 612, which acts on a lever 614, and when this plungeris in this centered position, the flow of pressurefluid from thehigh-pressure feed line 506 into either one of the conduits 164, 166, isblocked. Connected to the opposite ends of this valve plunger, at oneend through the lever 614, are the armatures 616, 618 of valve-operatingsolenoids 620, 622, having coils 624, 626. As will be apparent, when thesolenoid 620 is energized, the valve plunger 610 will be shifted to theleft, Fig. 13, thereby connecting the conduit 164 to the pressure supplyline 506 and the conduit 166 to an exhaust port 623, while if thesolenoid 622 is energized this valve plunger will be moved over to theright, thereby connecting the conduit 166 to the pressure supply lineand the conduit 164 to an exhaust port 625.

The jet reversing valve 564 actually is a double-purpose valve andserves to control both the transverse, or in-andout, and the vertical,or up-and-down, movements of the jack. Thus this valve has twointegrally formed valve plungers 630, 632 which are normally urged tothe left, Fig. 13, by means of a coil spring 634. When this double valveplunger is in this position, the conduits 148, are connected to thecylinders 146, and the conduits 140, 142 are directly connected to thecylinder 106. However, when this valve plunger is moved to the right,against the resistance of spring 634, the conduits 148, 150 are shut offfrom the cylinders 146 and the connection between the conduits 140, 142and the cylinder 106 are reversed. For thus shifting this double-actingplunger, there is connected to one of its ends the armature 636 of asolenoid 638, having a coil 640. The auxiliary transverse feed valve 566has a plunger 650 which is normally held in a centered position by meansof a spring-operated centering plunger 652, which acts on a lever 654,and when this plunger is in this centered position, the flow of pressurefluid from the high-pressure feed line 506 into either one of theconduits 148, 150 is blocked. Connected to the opposite ends of thisvalve plunger, at one end through the lever 654, are the armatures 656,658 of valve-operating solenoids 660, 662, having coils 664, 666. Aswill be apparent, when the solenoid 660 is energized, the valve plunger650 will be shifted over to the left, Fig. 13, thereby connecting theconduit 148 to the pressure supply line 506 and the conduit 150 to anexhaust port 663, while if the solenoid 662 is energized this valveplunger will be moved over to the right, thereby connecting the conduit150 to the pressure supply line and the conduit 148 to an exhaust port665. The rotation shut-oil valve 568 has a rotary plug 670 provided withan operating arm 672 and a port 674. Connected to the arm 672 is thearmature 678 of a solenoid 680, having a coil 682. When this solenoid isenergized, the plug 670 17 will be rotated to a position in which theflow of pressure fluid through the conduit 518 to the rotation jet relay324 is blocked.

The sequence valve 508 has a hollow valve plunger 690 which is slidablymounted in a cylinder 692 and provided with five ports 694, 696, 698,700 and 702. These ports are so arranged that, as the plunger 690 ismoved to the right, from the position in which it is shown in Fig. 13,the five supply lines 514, 516, 518, 526i and 521 are successivelyconnected to the high-pressure feed line 504 until, when this plungerreaches its limit of movement to the right, as determined by engagementwith the end of the cylinder 692, all of these supply lines areconnected to the high-pressure line 564. Movement of this valve plungeris effected by fluid under pressure from the line 510 under the controlof the pilot valve 512. The pilot valve has a plunger 704 which isnormally held in the position shown in Fig. 13 by means of a coil spring706 and, when this valve plunger is in this position, the sequence valveplunger 690 is urged to the left and to the position in which it isshown, thereby shutting off the feed lines from the high-pressure supplyline, by fluid under pressure admitted to the right-hand end of thecylinder 6% through a passageway 7458. For moving the pilot valveplunger 704 to the left, against the resistance of the spring 706, thereis connected to one of its ends the armature 714) of a valve-operatingsolenoid 712, having a coil 714. When this solenoid is energized, thevalve plunger 704 will be shifted over to the left thereby causing thesequence valve plunger 690 to be moved to the right by fluid underpressure admitted to the left-hand end of the cylinder 692 through apassageway 716.

As will be explained below, during a certain portion of the automaticoperating cycle of the herein illustrated machine, it is necessary tolimit the movement of the valve plunger 691' of the sequence valve 508to the left in such a way that it stops in a position in which only thesupply line 514 is connected to the high pressure line 564. For thispurpose, the valve 690 has a piston rod 718 which extends out throughthe housing of the sequence valve 508 and is provided with an enlargedend portion 720. Slidably mounted in a guideway on the sequence valvehousing is a stop bar 722 which, when the valve plunger 690 is in theposition shown in Fig. 13, rests on the enlarged end portion 729 of thevalve rod 718 and, as the valve plunger is moved to the right, this stopbar drops down onto the piston rod 718. Now, when the valve plunger 690is moved to the left, this bar engages the shoulder formed between theenlarged end portion 720 and the valve rod 718 and brings the sequencevalve plunger to a stop in a position in which only the plunger 696 tomove to the position in which it is shown in Fig. 13, there is connectedto this bar the armature 724 of a solenoid 726, having a coil 728.

For controlling the several solenoids which have been mentioned, tooperate the several valves and other members actuated thereby, theelectrical control system illustrated in Fig. 14 is provided. Thiselectrical control system includes, in addition to the solenoids,numerous switches and electrical relays the operation of which will beexplained below. Briefly described, however, this electrical controlsystem includes two high-voltage supply lines 390, 8&2 which areconnected, through a stepdown transformer S94 and power switch 89-6, totwo lowvoltage lines 898, 810, and directly to two high-voltage lines311, S12. Connected across the low-voltage lines are six parallelcircuits indicated generally by reference characters 814, 816, 818, 820,822 and 824. It will be more convenient to describe this electricalcontrol system in detail in connection with the description of acomplete operating cycle of the machine, which is to be presently setforth. However, before entering into this description, certain otheraspects of the herein illus is loaded onto the supporting member 100,thereby to locate the breastline of the shoe S on the holder in apredetermined position relatively to the supporting member Nil.symmetrically disposed, with respect to the end faces on the member 100,and secured thereto are two stop plates 830, 832 which, at times, duringan op-- erating cycle of the machine, are adapted to engage, andactuate, two limit stop arms 834, 836. These two limit stop arms areeach pivotally mounted on the lower side of the shelf portion 30 of themachine frame and extend outwardly therefrom so that their outer endsare in the zone of movement of the supporting member and the stop plates8%, $32 which are carried thereby. Asso ciated with the arm 834', is aright limit stop double pole switch 838, which is normally in theposition shown in Fig. 14, while associated with the stop arm 836 is aleft limit switch 840, which is normally closed, as shown in Fig. 14.These two switches are held in these positions by means of springs, notshown, associated with the limit stop arms 834, 836, and these springsare arranged to swing the outer ends of these arms toward each other,and toward the supporting member 100, to a limited extent as permittedby stops, not shown. As will appear below, the inseaming operation isinitiated as a result of the displacement of the switch 838 from theclosed position shown in Fig. 14 to its other closed posistop switch 840by engagement of the same stop plate with the stop arm 836. During theinsearning operation, the supporting member 1%, shoe holder 102 and shoeS thereon, are rotated through an angle of approximately so that theposition of the shoe is substantially reversed from that shown inFig. 1. The two stop arms are symmetrically disposed on each side of,and are spaced from the insearning instrumentalities in such a way thatthe insearnin operation which is started at the breastline on one sideof the shoe terminates at the breastline on the opposite side of theshoe. As will presently appear, after the insearning operation has beenconcluded and certain operations of the inseaming head effected, thejack is moved inwardly and downwardly to a location in which the shoe Sand the supe., from 834, 836

end of the largest size of shoe extends beyond the active stop plate, i.e., plate 830 in Fig. 1. Thus, there is no danger, regardless of thesize of the shoe being inseamed, that the idle stop plate will ever comeinto engagement with the stop arm 336 during the insearning operation l9along thefirst side of the shoe to beinseamed. When the toe end of theshoe is reached, the position of the shoe is reversed so that the activeplate 834! is faced toward this stop arm. As will be apparent, inasmuchas the extent of the feeding movement of each shoe is determined by thefeelers 218, 3%, 3% and the insole rib R, the herein illustrated machineautomatically accommodates itself to shoes of different sizes. Thus,regardless of the size of the shoe, the inseaming operation will alwaysstart at the breastline on one side and end at the breastline on theopposite side.

Referring to Fig. 13, connected to the supply line 514 is a branch line856 which leads to a cylinder 852 in which there is a piston 854. Thispiston and cylinder are associated with the supporting member 109 of thejack and, when fluid under pressure is admitted to the cylinder 852, thepiston 85 operates a pair of locking plates 853, Fig. l, which clamp theshoe holder 1G2 firmly in place on the supporting member 1%. Located inline with the enlarged end 720 of the piston rod 718 of the sequencevalve plunger 69% are two switches 860, 862, see Fig. 14, which arenormally held open, by means of springs, not shown, when the sequencevalve plunger is in the position shown in Fig. 13. Also located adjacentto the sequence valve is a third switch 864. likewise held open by a.spring, not shown, when the plunger 690 is in the position shown in Fig.13. Upon movement of the sequence valve plunger to the right, thesethree switches are all closed, switches S613, ssz by the end 720directly and switch 864 by means of a cam block secured to the end 720of the sequence valve piston rod.

As will be understood by reference to the patent to Merrill, No.1,971,575, mentioned above, the inseaming head 20 is controlled by acontrol rod (68) which is moved upwardly by means of a foot treadle, toengage a forward driving clutch for operating the machine in the normalway, see page 2, column 2 of the mentioned Morrill patent. This rod isalso moved downwardly by the action of a spring, when the foot treadleis released, to engage a low-speed reverse drive mechanism which causesthe inseaming machine to go through what is called its back up cycle andcome to a stop with the needle 41 and awl 42 withdrawn from the work. Itis during this back up cycle that the thread T is cut and held, by thethread knife 7 4 and thread-gripping member '7 and thread holder 46, thewelt W cut by the welt knife 72, which is first advanced to cut the weltand then retracted, and the weltadvanced by the welt-advancing finger76, in the manner explained more particularly in the patent to Morrill,No. 2,359,662, also referred to above. In the herein illustratedmachine, the foot treadle is replaced by a clutch-operating solenoid879, having an armature 872 which is operatively connected to thecontrol rod, diagrammatically illustrated in Fig. l4, and a coil 874.This coil is arranged to be connected to the high voltage lines 811, 812by means of a relay 876 having a switch part 878 and a coil 88% As willbe seen from Fig. 14, the coil 880 of this relay is in the cross circuit816 and is under the control of the switch 864.

It will be appreciated that the orientation of the cross slides 108 andllii will be substantially reversed during each automatic operatingcycle of the machine. As will appear below, prior to and after theinseaming operation, the shoe is moved longitudinally, i. e., istraversed, and is moved transversely, by pistons 152 and 144, bypressure fluid admitted to cylinders 154 and 145, from the line 506through the auxiliary longitudinal feed valve 562 and the auxiliarytransverse feed valve 566, respectively. Inasmuch as these traversingand transverse movements of the shoe must take place in the samedirection, despite the reversal in orientation of the cross slides 108,110,'the valve-operating solenoids 620, 622 and 660, 662 are under thecontrol, respectively, of a longitudinal feed selector switch 899 and atransverse feed selector switch H 892. These switches are double-poled,as shown in Fig.

868, adjustably energized.

. the axis y v until the 20 l4, andare alternately shifted, as theorientation of the: cross slides is reversed, by means of a cam 894which is: secured to the shaft portion 2:38 of the rotary jet receiver.-248, see Fig. 8.

With the exception of the action of certain safety devices, which willbe explained below, a complete operat ing cycle of the machine will nowshoe S on its holder 102 has been loaded onto the sup-- porting member16% of the jack, the operator momentarily closes a starting switch 900,Fig. 14, which causes a relay 9%, having a coil 9134 and switch part906, to-

close and hold, since the right limit arm $34 is free and the switch 838is held in the position shown. The jack now moves to the right, i. e.,traverses, under the control of the auxiliary longitudinal feed valve562 whose plunger 619 is shifted in the proper direction, from itscentered position, by one or the other of the solenoids 624 622,selected by the auxiliary feed selector switch 8% under the control ofthe earn 894. At this point in the automatic cycle, solenoid 606 isdeenergized, inasmuch as the cross circuit 818 is open so that theplunger 600 of the feed shut-off valve 566 is in closed position. Whenthe jack is moved to arm 834 is engaged by one or the other of the stopplates- 336, 832, say 836 for example, the contacts of the doublepoleright limit switch 838 are reversed. This opens the cross circuit 824and releases the relay %2 together with solenoid 620 or 622, thusallowing the valve plunger 610 of the auxiliary longitudinal feed valveto be returned to its centered and closing position. Also, a'relay 910,having a coil 912, in the cross circuit 822, and a switch member 914, isenergized, through the left limit switch 849, which, of course, wasclosed by its spring when the left limitarm 836 was released as a resultof the movement of the jack to the right. The energizing of the coil 912of the relay 9') causes the switch member 914 to move down from theposition in which it is shown to a position in which the coil 714 of thesolenoid 712 is This solenoid now shifts the valve plunger 7G4 of thepilot valve 512 to the left thereby causing the sequence valve plunger6% to be shifted to the right.

As the sequence valve plunger is I right, fluid under pressure from thehigh" pressure line 504 enters the jet relays in the following order:Elevation jet relay 21%, through line 514, jack moves upwardly untilfeeler 228 is elevated by the shoe S to center the jet nozzle 2Z2;longitudinal and transverse jet relay 238 through line 516, jack movesoutwardly until the feelcr 218, which engages the insole rib R, centersthe jet nozzle relatively to the openings 242, 242, of the jet receiver,Fig. 9, valve $61) still remaining closed so that no longitudinal feedoccurs at this time; rotation jct relay 324 through line 518, shoerotated about the axis zz until the feeler 304 which engages the insolerib R centers the jet nozzle 32.2; pitch jet relay 344 through line 520,shoe rotated about axis until the feeler Bill which also engages theshoe bottom, centers the jet nozzle 342; and roll jet relay 368 throughline 521, shoe rotated about tom of the shoe centers the jet nozzle 366.

I As the sequence valve plunger completes its opening movement to theright, the switches see, 862 and 864 will be closed and the shoe S willhave been properly positioned relatively to the operatinginstrumeutalities of the inseaming head. Also, the shoe holder 162 beenclamped to the supporting member ltlll by the piston 854 as a result ofthe admission of fluid under pressure to the line 514 leading to theelevation iet 21%. The closing of the switch 556% bringsin the crosscircuit 820 together with certain safety features which will be mentioned below, while the closing of the switch 862 brings in the crosscircuit 818 and energizes the solenoid 696, thereby causing thelongitudinal feed shut-off valve plunger The closing of the switch 864brings in cross circuit 816 be described. After a. I

the right to an extent where the right limit shifted over to the feeier36ft which engages the bot will have.

668 to be moved to the left to itsopen positionof the relay 876, therebycausing its switch member 878 to close and energize the coil 874 of thesolenoid 87! This solenoid moves the control rod 68 of the inseaminghead upwardly to engage the forward driving clutch and start theoperation of the inseaming instrumentalities. Inasmuch as thelongitudinal feed of the jack does not start until the feed shut-offvalve 560 is opened, as a result of the closing of the switch 862, andsince the operation of the inseaming head is initiated by the closing ofthe switch 864, an exact timing between the shoe feed and inseamingaction can be obtained by adjustment of the cam 868 on the enlarged end726 of the sequence valve piston rod.

As the inseaming operation proceeds, the jack moves to the left and, atthe beginning of this movement of the jack, the right limit arm 834 isreleased thereby permitting the right limit switch 838 to return to theposition in which it is shown in Fig. 14. However, the cross circuit 824will now remain open inasmuch as the starting switch 930 will have beenpreviously released by the operator. Accordingly, neither one of theauxiliary longitudinal feed solenoids 620, 622 will be energized. Whenthe in seaming operation has proceeded to the breastline on the oppositeside of the shoe from the starting point, the stop plate 830 will engagethe left limit arm 836 and open the left limit switch 840. This releasesthe relay 910 and causes its switch member 914 to return to the positionshown in Fig. 14. Cross circuits 820, 822 are now opened and the coil714 of the pilot valve solenoid 712 is deenergized. Hence,

and energizes the coil 880 valve stop solenoid 726 is at this timedeenergized, such return movement of the sequence valve is arrested bythe stop bar 722 in a position in which all of the supply lines leadingto the several jet relays are shut off except the line 514 which leadsto the elevation jet relay 210. The return of the sequence valve plunger690 also permits switches 360, 862 and 364 to open thereby cutting outthe safety features associated with the cross circuit 820 anddeenergizing the solenoid 606 and relay 876. The longitudinal feedshut-off valve 560 now closes and the switch 873 of the relay 8'76opens, thereby deenergizin the solenoid 876. Thus the control rod or"the inseaming head is released for downward movement by its associatedspring to bring the inseaming operation to a stop and to cause theinseaming head to go through it back up cycle.

As pointed out above, during this back up cycle, the thread T is cut andheld by the members 46, 7t), 74, see Fig. 12, and the welt knife 72 isadvanced to cut the welt W and then retracted, after which the welt isadvanced by the welt-advancing point 76, in the manner explained moreparticularly in the patent to Morrill No. 2,359,662. As the welt knife72 returns, it momentarily closes a switch 920 thereby energizing thecoil 921 of a relay 922 having a switch member 924. This relay isadapted, when its coil is energized momentarily, to cause the switch 924to close and, after a predetermined time interval, to open. The closingof this switch brings the solenoid 63S, switch 892, solenoids 660 or662, and another solenoid 926, having an armature 928 and a coil 930,into the cross circuit 814. As the solenoid 638 is energized, the doubleplunger of the jet-reversing valve 564 is moved to the right, Fig. 13,while the energizing of solenoid 660, or 662, as selected by the switch892 under the control of the cam 894, Fig. 8, causes the auxiliarytransverse feed valve plunger 650 to be shifted from its centeredposition. Hence, the jack is moved inwardly, by the piston 144, anddownwardly, by the piston 194-, these movements being directly oppositeto those called for by the feeler 218, which is now released to theaction of springs 224, 226, and by the jet relays 23S and 210. In thisconnection, it will be noted that the jet relay 238 is now shut off fromthe cylinder 146 by the valve plunger 630 of the jet-reversing valve sothat the transverse movement of the jack is controlled by the auxiliarytransverse feed valve 566, while the connections between the elevationjet 210 and the cylinder 106 are reversed by the valve plunger 632.Also, of course, the jet relay 238 is shut 01f from the cylinder 154 bythe plunger 600 of the feed shut-off valve 560.

The extent of downward movement of the jack is limited by the engagementof the piston 104 with the bottom of the cylinder 106 while the extentof inward movement of the jack is determined by a locking bar 929 whichis adapted to engage a locking recess 932 formed in one of the pistonrods associated with the pistons 144, see Fig. 13. This locking bar isconnected to the armature 923 of the solenoid 926, by means of a lever934, which solenoid is, as already noted, energized at the same time asthe solenoids 638 and 660 or 662 The locking recess 932 is so disposedthat when the locking bar 929 is urged into this recess, against theaction of a coil spring 931 by the solenoid 926, the transverse inwardmovement of the jack will be arrested with the feelers 218, 300 and 369substantially centered with respect to the two ends of the insolev rib Rat the opposite sides of the shoe, adjacent to the breast line. At theend of the time delay, the relay 922 releases and opens the circuit 814thereby deenergizing the solenoids 638, 660 or 662 and 922. As thedouble plunger of the jet-reversing valve 564 is returned by its spring634, the armature 636 of the solenoid 638 momentarily closes a switch946 which energizes the coil 724 of the solenoid 726. The sequence valvelocking bar 722 is now elevated to permit the sequence valve 690 toclose fully, thus completing the operating cycle.

Referring to Figs. 6 and 7, as has been explained above, the linear rateof feed of the shoe by the jack is exactly matched to the rate of feedof the awl 42 and needle 40 of the inseaming head by means of mechanismincluding the roller 432 against which the welt W is pressed by theroller 444. During the back-up cycle of the inseaming head, when thewelt W is advanced by the welt-advancing point 76, see Fig. 12, theaction of the roller 4 44 is suspended and this roller is moved bodilyaway from the roller 432 thereby entirely freeing the welt. For thusoperating the roller 444, the setscrew 458 is, as already mentioned, inengagement with an axially movable plunger 459 which is associated withthe cam shaft 52 of the see Fig. 6. When the cam shaft 52 is tion, andbefore this shaft is succeeding back-up cycle of the inseaming head,this plunger is moved axially in the cam shaft in a direction extendingdownwardly as viewed in Fig. 6, by means of mechanism not hereinillustrated but which is described in United States Letters Patent No.2,220,112, issued on November 5, 1940, in the name of Alfred R. Morrill.As a result of such movement of this plunger, the roller 444 will bedrawn av ay from the roller 432 through the action of lever arms 45th,456 and the link 454. When the inseaming head is again set intooperation, this plunger hold it against the roller 432.

As suggested above, the automatic control system is provided 23 and 864will be closed by the fully opened sequence valve plunger 690, see Fig.13. The closing of any one of these three safety switches immediatelyenergizes the coil 960 of the relay 062 and also the coil 602 of thesolenoid 680. The switch part 064 of the relay 962 now opens the circuitto the relay 910 and also to the solenoid 712 and closes the circuitthrough solenoid 726. The opening of the circuit to the solenoid 712 andthe closing of the circuit to the solenoid 726 causes the sequence valveplunger 690 to close fully thereby shutting off the supply of pressurefluid from all five of the jet relays 210, 231i, 324, 344 and 368 andbringing the jack to. a stop. In addition, the flow of pressure fluid tothe jet relay 324 is shut ofi immediately by the valve plug 670 which isturned to its closed position by the armature of the solenoid 680. Thisarmature is also connected to a lever 970 which carries a stop member972, diagrammatically illustrated in Fig. 14, and when the solenoid 680is energized, this stop is interposed between a fixed part 974 of theinseaming head 20 and a collar 976 secured to the control rod 68 of theinseaming head. The opening of the switch 864 results in thedeenergizing of the solenoid 370 so that the control rodcan be moveddownwardly by its associated spring to an extent which is limited by thestop 972 and is just sufiicient to bring the inseaming head to a stopwithout, however, causing it to go through its back-up cycle. Thus, theautomatic operation of the inseaming head and the movements of the jackwill be terminated as a result of the momentary closing of any one ofthe switches 950, 952 or 954.

In order to restart the inseaming head and movements of the jack aftertermination in the above manner, a reset switch 980, which is inparallel with the right limit switch 838, is provided, see Fig. 14. Theclosing of this reset switch has the same result as the movement of theswitch 833 to the right by the traversing of the jack. However, beforethis reset switch is closed, it is necessary for the operator manuallyto open the valve 568 and, by doing this, he also withdraws the stopmember 972 from its operative position.

The safety switch 950 is provided for the purpose of bringing the jackto a stop and terminating the operation of the inseaming head inresponse to breakage, or loss of tension of the thread T. Accordingly,this switch is associated with the thread tension mechanism, not shown,but which may be of the same general construction as that disclosed inthe patent to Merrill No. 2,359,662, mentioned above. Thread-tensioningmechanism of this type may include a pivotally mounted arm (forexamplesee the arm 770 of the Morrill machine) which is held in apredetermined angular position, against the action of a spring, by thetensioned thread. Upon breakage, or loss of tension of the thread, thisarm will be moved to a different angular position by its associatedspring and the switch 950 is so located as to be closed by this arm whenit is so moved by its spring. The switch 952 is provided for the purposeof bringing the jacl; to a stop and terminating the operation of theinseaming head in response to the feeler 300 jumping the insole rib R.This feeler controls both the rotation of the jack about the verticalaxis z-z and its rotation about the horizontal axis x-x (i. e., pitch).Inthe event that this feeler should, for any reason, jump over theinsole rib, the jack will immediately start to rotate in acounterclockwise direction about the vertical axis z-z and this feelerwill quickly drop to its lowermost position as it passes beyond the weltW. Accordingly, the switch 952 will be located closely adjacent to theupper end of the arm 302 which is associated with this feeler so that itis closed by this arm when the feeler 300 drops ito its lowermostposition. The switch 954 is a manual stop switch which is located in aconvenient position for the use of the operator who, by closing thisswitch momentarily, can immediately bring the movements of the jack to astop and terminate the operation of the inseaming head.

As has been pointed out above, the shoe S being inseamed is mounted onthe shoe holder 102 which is received in a supporting member 100 andlocated, relatively to the supporting member, by means of a stop carriedby the shoe holder. It has already been explained that the stop on theshoe holder is adapted to engage one or the other of the two end faceson the supporting member so as to locate the breast line of the shoe ina predetermined position relatively to one of two stop plates 330, 832associated with the supporting member. Referring particulraly to Figs. 2and 3, the shoe holder 102 comprises a base 1000 which is formed, on itslower side with inclined guide surfaces 1002, 1002 which are adapted tofit into correspondingly shaped guiding surfaces on the upper end of thesupporting member 100. Pivotally mounted, adjacent to one end of thebase 1000, is a lever 1004, one arm of which is shaped to form a lastpin 1006, and a compression spring 1008 is arranged to swing this leverin a clockwise direction as viewed in Fig. 2 and to the extent permittedby a locking plunger 1010, see Fig. 4, which is siidably mounted in thebase 1000. This locking plunger has a wedge surface 1012 whichterminates in a notch 1014 and the lever 1004 is formed with a narrowrib 1016, adapted to fit into the recess in the locking plunger when theparts are in the positions shown in Fig. 4-. A coil spring 1018,interposed between one end of the locking plunger and a side plate 1020,tends to urge the plunger to the right, Fig. 4, when this plunger isreleased by withdrawal of the rib 1016 from the notch 1014, and, as thisplunger is moved to the right, the

last pin 1006 will be rocked in a clockwise direction,

as viewed in Fig. 2.

The base 1000 of the shoe holder is cut away as indicated by the dottedline 1022 in Fig. 2 and, at the righthand end of the cut-away portionthe base extends upwardly to form an abutment 1026 on the upper side ofwhich there are two inclined dovetail guiding surfaces 1023, 1028, seeFig. 3. Slidably supported on these guiding surfaces is a block 1030,provided with a movable side piece 1032, and associated with this sidepiece is a clamp screw 1034 which is threaded into a nut 1036 andprovided with an operating handle 1038. Mounted for vertical slidingmovement in the block 1030 is a toe pad 1040 and associated with thispad is a locking nut 1042. Extending outwardly from the opposite sidesof the block 1030 are a pair of flanges 1044, 1046 and pivotally mountedbetween these flanges are a pair of arms 1048, 1048 which carry, attheir upper ends, shoe-centering pads 1050, 1050. At their lower ends,these arms are provided with rounded portions 1052, 1052 which are heldin engagement with wedge surfaces 1054, 1054, see Fig. 5, formed on theends of locking bars 1056, 1056, by means of compression springs 1058,1058. These locking bars are slidably mounted in grooves 1060, 1060, cutin the base 1000, and are urged in one direction, i. e., to the right asviewed in Fig. 5, by means of coil springs 1062, 1062, interposedbetween the ends of bores in these bars and end plates 1064, 1064,secured to the base. Formed integrally with these locking bars areoutwardly extending arms 1066 which have end portions 1068, 1068 ofreduced size, and these end portions project beyond the opposite sidesof the base 1000, see Fig.5. Fitted in a dovetail groove 1070, cut inthe lower side of the base 1000, is a stop member 1072, Fig.

4, and formed along one side of this stop member are a series of ratchetteeth 1074, Fig. 5. Pivotally mounted on the base 1000 is a pawl 1076having a pointed end 1078 which is normally urged into engagement withthese teeth by means of a compression spring 1080. A portion 1082 ofthis pawl projects beyond the side of the base 1000 for engagement bythe operator to release the

